1994 SSE no power in 2nd gear

I just bought a 94 SSE w/126k

while driving home I floored it to pass and was very disappointed with the power.
in fact the RPM's went up to around 4000 but there was no power/pull.
as soon as I lifted and it shifted into 3rd - rpm's dropped and it pulled like I know it should.
I only notice this condition while at speed.

what could be going on in the transmissioin to cause this condition?
electronic?
mechanical?
hydrolic?

please help!

ttt

any thoughts?